KR20190124150A - Coating apparatus and method for producing coating film - Google Patents

Abstract

The present invention provides a coating apparatus capable of effectively forming a coating film in which a thickness change in the width direction is fully inhibited. The coating apparatus has a die for coating a coating liquid to a relatively moving material to be coated. The die has the identical shape and size of the cross section of a manifold seen from the width direction over the width direction. An end edge on a slot side of the manifold is formed in a secondary curve shape determined from the specific formula.

Description

Coating apparatus and manufacturing method of coating film {COATING APPARATUS AND METHOD FOR PRODUCING COATING FILM}

TECHNICAL FIELD This invention relates to the manufacturing method of a coating apparatus and a coating film.

Conventionally, for example, a die coater is known as one kind of coating apparatus. A die coater is a coating apparatus which forms a coating film on a to-be-coated object by discharging a coating liquid from a die on to-be-coated objects, such as a base material which moves relatively. In such a coating apparatus, a die has a manifold which has an inlet port and sends the coating liquid which flowed in from the inlet port toward at least one end part in the width direction of a workpiece, and communicates with the manifold, It has an open slot at the leading edge.

In this type of coating device, a manifold is formed over the width direction of the workpiece, and the distance (length of the slot) between the leading edge of the slot and the slot-side end edge in the manifold is measured. If the same across the width direction, the more the coating liquid is directed from the inlet of the manifold to the end, the greater the pressure loss in the manifold and the slot. Due to this, the flow rate of the coating liquid discharged from the slot decreases toward the end from the inlet port, and the thickness of the coating film formed decreases.

Therefore, for example, a technique is known in which a manifold having an inlet at one end in the width direction and formed to send a coating liquid from the inlet to the other end is designed in a specific shape. Specifically, the flow rate of the coating liquid discharged from the slot is formed by forming the slot side end edge in the manifold so that the length of the slot becomes smaller on the secondary curve from one end in the width direction of the manifold to the other end. A technique for bringing uniformity closer to the other end from the one end is proposed (see Patent Document 1).

Japanese Patent Laid-Open No. 2002-72409

However, in the coating device as described above, it may take a great deal of effort and time to properly determine the shape of the slot side end edge of the manifold, and may not be able to determine it. This leads to the inability to fully suppress that the thickness of coating liquid fluctuates in the width direction.

This invention makes it a subject to provide the coating apparatus and the manufacturing method of a coating film which can form the coating film in which the fluctuation | variation of the thickness was fully suppressed in the width direction in view of the said situation.

MEANS TO SOLVE THE PROBLEM The present inventors earnestly researched in order to solve the said subject, and discovered the following knowledge.

Specifically, the coating liquid introduced into the manifold is each virtual path flowing through the manifold and flowing out of each predetermined position into the slot, and passing through the slot at the shortest distance and discharged from each position of the opening of the slot. Suppose you are following a virtual path. In addition, it is assumed that the coating liquid discharged from a slot is a collection of coating liquid discharged from the opening of a slot along each virtual path | route. In addition, it is assumed that each flow velocity in the opening of the slot in each virtual path is the same value between each virtual path over the width direction (for example, in FIG. 6, S ₀ = S ₁ = S ₂ ... = S _M ).

Voltage loss of the coating liquid discharged from the opening of the slot along each virtual path becomes the same between each virtual path from the general common sense of physics.

Therefore, based on the assumptions concerning the flow velocity, the distance between the outlet position and the discharge position (the distance between the slot side end edge of the manifold and the opening of the slot, i.e., the slot length) and known parameters, When the voltage force loss in the virtual path can be formulated, it becomes possible to calculate the length of each slot at each position so that the voltage force loss in each virtual path is equal to each other between the virtual paths.

Then, a graph in which the calculated slot lengths are plotted for each discharge position is created, and a second approximation curve is calculated from this graph. The slot side end edge (slot side end edge) of the manifold is formed so as to have a shape along the calculated second approximation curve, and the shape and size of the cross section of the manifold viewed from the width direction is in the width direction. The manifold is formed to be identical throughout. Thereby, the flow velocity of the coating liquid discharged | emitted from a slot can be made to approximate the same value over the whole slot (the whole width direction of a to-be-coated object).

As described above, using the equation calculated based on the assumption that the flow rates are the same between each virtual path, and that the shape and size of the cross section of the manifold are the same over the width direction, the voltage loss of each virtual path is reduced. Determine each slot length to be constant. Manifolds and slotted dies are used to form a shape along a second order approximation curve obtained from each determined slot length. As a result, it was found out that a coating film having a small variation in thickness could be formed over the width direction, and thus the present invention was completed.

That is, the coating apparatus which concerns on this invention,

A coating device having a die for coating a coating liquid on a relatively moving workpiece,

The die,

A manifold having an inlet through which the coating liquid flows and sending the coating liquid introduced from the inlet toward the width direction of the workpiece;

Has a slot in communication with the manifold and having an opening at the leading edge of the die,

The shape and size of the cross section of the manifold seen from the width direction are the same over the width direction,

The opening of the slot extends along the width direction,

The end or center of the width direction of the area | region in which the said coating liquid in the said opening is discharged | emitted from the said slot is set as an origin, and the x-axis is set along the opening from the origin in the direction which the coating liquid is sent to, When the y axis is set in the direction perpendicular to the x axis from the origin,

The slot-side end edge of the manifold is formed in a shape drawn by a quadratic curve represented by the following formula (1),

The coating liquid introduced from the inlet into the manifold flows out of the slot side end edge into the slot at a plurality of outflow positions arranged in the width direction and passes through the slot in a direction parallel to the y axis. Is assumed to follow each virtual path discharged from a plurality of discharge positions of the opening,

In the virtual path at the mth (m is an integer of 0 or more) from the origin, the distance from the origin to the discharge position is x _m [m], and the total pressure loss of the coating liquid from the inlet to the opening is ΔP. _m [Pa], when the distance between the outlet position and the discharge position is represented by L _m [m], respectively,

The relationship between the ΔP _m and the L _m is represented by the following formulas (2) and (3),

While satisfying the above formulas (2) and (3), each L _m is calculated such that each ΔP _m in each virtual path is equal to each other between the virtual paths, and each calculated L _m and the corresponding L _m The quadratic approximation curve of the graph in which the relationship of x _m corresponding to is plotted and configured to determine the quadratic curve.

A, B, C: Coefficient [-]

W: Coating width [m]

Q ₁ : Flow rate of coating liquid flowing into manifold [㎥ / s]

Q ₂ : Flow rate of coating liquid flowing out of manifold other than slot [㎥ / s]

S: flow rate of coating liquid discharged from slot (S = (Q ₁ -Q ₂ ) / W) [m 2 / s]

h: slot height [m]

R: Radius of manifold [m]

n _c : first viscosity parameter [-] of the coating liquid in the manifold

η _c : second viscosity parameter [-] of the coating liquid in the manifold

n _s : first viscosity parameter [-] of the coating liquid in the slot

η _s : second viscosity parameter [-] of the coating liquid in the slot

The above configuration will be described in detail. The above formula derived based on the assumption that the shape and size of the cross section of the manifold seen from the width direction are the same across the width direction, and that the flow rates of the coating liquid discharged from the openings of the slots between the respective virtual paths are the same values. (2) and equation (3) are used. Thereby, so that each ΔP _m represented by the known parameter and the unknown distance (slot length) L _m between the outlet position and the discharge position (ie, the opening) is equal to each other between the virtual paths, Each L _m is calculated. Based on the calculated angle L _m , a quadratic approximation curve is determined. Slot side end edges of the manifold are formed to follow this quadratic approximation curve. In addition, in accordance with this end edge, the manifold is formed so that the shape and size of the cross section viewed from the width direction are the same over the width direction.

By forming the manifold in this manner, the flow rate of the coating liquid discharged from the opening of the slot can be made close to the same value over the width direction of the workpiece. Therefore, the fluctuation | variation of the thickness of the coating film formed can be suppressed over the width direction.

Moreover, since the said 2nd approximation curve can be determined from a known parameter, it is efficient.

Therefore, the coating film in which the fluctuation | variation of the thickness was fully suppressed in the width direction can be formed efficiently.

The manufacturing method of the coating film which concerns on this invention is equipped with the process of discharging a coating liquid on the to-be-moved coating object using the said coating apparatus, and forming a coating film.

According to such a structure, since the said coating apparatus is used, the coating film in which the fluctuation | variation of thickness was fully suppressed in the width direction can be formed efficiently.

BRIEF DESCRIPTION OF THE DRAWINGS The schematic side view which shows the coating device of one Embodiment of this invention.
Fig. 2 is a schematic plan view showing an example of a die manifold and a slot provided in the coating apparatus of the present embodiment together with the flow of the coating liquid from the manifold to the slot.
3 is a schematic side view illustrating a die of the present embodiment.
FIG. 4 is a schematic plan view schematically showing each virtual path of the coating liquid in the manifold and slot of FIG. 2 and the pressure loss in each virtual path. FIG.
5 is a graph showing an example of a viscosity curve of a coating liquid.
FIG. 6 is a schematic plan view schematically showing each flow rate from an opening of a slot in each virtual path of the coating liquid of FIG. 4. FIG.
FIG. 7 is a schematic plan view schematically showing the slot length in each virtual path of the coating solution of FIG. 4. FIG.
Fig. 8 is a graph showing an example of the relationship between the distance from the origin in the x axis direction and the slot length in each virtual path.
9 is a schematic view showing an example of the shape of the cross section of the manifold and the cross section radius;
FIG. 10 is a schematic diagram schematically showing each virtual path of the coating liquid in the manifold and the slot of the die included in the other coating apparatus of the present embodiment, and each flow rate from the opening of the slot in each virtual path. Floor plan.
11 is a schematic plan view schematically showing each virtual path of the coating liquid in the manifold and the slot of the die included in the other coating apparatus of the present embodiment, and the respective flow rates from the opening of the slot in each virtual path. .
FIG. 12 is a schematic plan view schematically showing the slot length in each virtual path of the coating liquid of FIG. 11. FIG.
13 is a schematic plan view showing an example of a manifold and a slot of a die provided in another coating apparatus of the present embodiment together with a flow of the coating liquid from the manifold to the slot.
FIG. 14 is a schematic plan view schematically showing each virtual path of the coating liquid in the manifold and the slot of FIG. 13 and each flow rate from the opening of the slot in each virtual path; FIG.
FIG. 15 is a schematic plan view schematically showing the slot length in each virtual path of the coating solution of FIG. 13. FIG.
The graph which shows the viscosity curve of the coating liquid used in Example 1. FIG.
Fig. 17 is a graph showing an example of the relationship between the distance from the origin in the x axis direction and the slot length in each virtual path of the first embodiment.
18 is a graph showing the relationship between the thickness of a coating film formed by the coating apparatus with a die having a manifold of Example 1 and the distance from the origin in the x-axis direction.
19 is a schematic plan view showing the manifold shape of the die of Comparative Example 1;
20 is a graph showing an example of the relationship between the distance from the origin in the x-axis direction and the slot length in each virtual path of Comparative Example 1. FIG.
Fig. 21 is a graph showing the relationship between the thickness of a coating film formed by a coating apparatus with a die having a manifold of Comparative Example 1 and the distance from the origin in the x-axis direction.
22 is a schematic plan view showing a shape of the die manifold of Comparative Example 2. FIG.
The graph which shows the relationship of the thickness of the coating film formed by the coating apparatus provided with the die which has the manifold of the comparative example 2, and the distance from the origin in the x-axis direction.

First, the coating apparatus of one Embodiment of this invention is demonstrated, referring drawings.

As shown in FIG. 1, FIG. 2, and FIG. 3, the coating apparatus 1 of this embodiment provides the die 5 which coats the coating liquid 33 on the to-be-moved object 31. FIG. It is a coating device 1 provided. Thus, the coating apparatus 1 provided with the die is called a die coater.

The die 5 is,

A manifold 9 having an inlet 10 through which the coating liquid 33 flows in, and both ends of the coating liquid 33 introduced from the inlet 10 in the width direction of the object to be coated 31. A manifold 9 which is directed toward at least one of the ends 9a, 9b,

It communicates with the manifold 9 and sends the slot 8 which has the opening 8a in the leading edge 5a of the said die 5, and the coating liquid 33 from the exterior to the inflow port 10. It has the supply part 11 which comprises a path | route.

In this embodiment, the inflow port 10 is formed in one end part (1st end part) 9a of the manifold 9, and the coating liquid 33 which flowed in from the said inflow port 10 has the other end part. The coating apparatus 1 (the said die 5) is comprised so that it may be sent toward (2nd end part) 9b.

The coating apparatus 1 is further provided with the solidification part 17 which forms each coating film 35 by solidifying the coating liquid 33 coated by the die 5. In addition, the coating apparatus 1 does not need to be equipped with the solidification part 17. FIG.

The coating device 1 further includes a support part 15 for moving the workpiece 31 relative to the die 5 in the longitudinal direction while supporting the workpiece 31 to the surface. . In addition, the coating device 1 may not be provided with the support part 15.

Although it does not specifically limit as the to-be-processed object 31, For example, a strip | belt-shaped sheet member etc. are mentioned.

As such a sheet member, a resin film is mentioned, for example. Moreover, as a resin film, the lumirror (trademark) made by Toray Corporation etc. is mentioned, for example.

The support part 15 supports the to-be-processed object 31 which moves in the longitudinal direction from the opposite side to the side in which the die 5 was arrange | positioned. The coating liquid 33 is coated on the to-be-processed object 31 which is supported by the support part 15 and moves relatively with respect to the die 5.

As such a support part 15, a roller etc. are mentioned.

In this embodiment, the support part 15 is arrange | positioned in the position which opposes the slot 8 of the die 5, and is relatively from the one (downward of FIG. 1) with respect to the said slot 8 (FIG. 1). 1 upward), it is comprised so that the to-be-coated object 31 may be moved.

The solidification part 17 is comprised so that the coating liquid 33 may be solidified and the coating film 35 is formed. By this solidification part 17, the solidified coating film 35 is formed. The solidification part 17 should just be what can solidify the coating liquid 33, and is not specifically limited. Such a solidification part 17 is set suitably according to the kind of coating liquid 33, etc.

The die 5 is configured to discharge the coating liquid 33 from the slot 8 and to coat the coating film 35 on the workpiece 31 that is relatively moving.

The die 5 is arrange | positioned so that the slot 8 may face to the side, and is comprised so that the coating liquid 33 may be discharged to the to-be-processed object 31 which moves in the up-down direction with respect to the slot 8, and have. The coating apparatus 1 supplies the coating liquid 33 to the die 5 from the accommodation part (not shown) of the coating liquid 33 via piping (not shown) and a pump (not shown). It is configured to be. In addition, the die 5 may be arrange | positioned so that the slot 8 may face downward or upward.

Specifically, the die 5 includes an upstream first dive lock 6 and a downstream second dive lock 7 disposed to face the first dive lock 6. The die 5 is formed by combining the first dive lock 6 and the second dive lock 7. By combining the dive locks 6 and 7 in this way, the manifold 9 in which the coating liquid 33 supplied by the pump (not shown) is stored between these, and the said manifold 9 ), The slot 8 and the supply part 11 which face toward the distal edge are formed. The gap between the leading edge of the first dive lock 6 and the leading edge of the second dive lock 7 serves as an opening 8a (discharge port) of the slot 8. The opening 8a extends along the width direction of the workpiece 31.

In FIG. 1, a die 5 having no shims is shown, and a die 5 of an embodiment in which the first dive lock 6 and the second dive lock 7 are assembled. In addition, you may employ | adopt the die 5 of the aspect by which the 1st dive lock 6 and the 2nd dive lock 7 are joined together through a shim.

The leading edge of the 1st dive lock 6 and the leading edge of the 2nd dive lock 7 are arrange | positioned so that it may be located on the plane perpendicular | vertical to the radial direction of the support part 15. As shown in FIG. The slot 8 is arrange | positioned in the direction parallel to the normal direction of the support part 15. As shown in FIG.

The manifold 9 is formed so that the shape and the magnitude | size of the cross section seen from the width direction of the to-be-processed object 31 may be the same across the said width direction.

Although the shape of the cross section of such a manifold 9 is not specifically limited, For example, as shown in FIG. 9 mentioned later, shapes, such as circular shape, semi-circle shape, fan shape, etc. may be sufficient. The size of the cross section of the manifold 9 is also not particularly limited.

The radius of the cross section of the manifold 9 will be described later.

In the coating apparatus 1 of this embodiment, the inflow port 10 is formed in the 1st end part 9a of the manifold 9 in one of said width directions, in detail. The coating liquid 33 is sent from the first end 9a toward the second end 9b. In addition, when the flat surface of the side in which the manifold 9 in the dive lock 6 (here, the first dive lock) is formed is viewed from the direction perpendicular to this surface, the opening 8a of the slot 8 is formed. The edge part of the width direction of the area | region (coating area | region F) by which the coating liquid 33 in () is discharged | emitted from the slot 8 is set to origin zero. From this origin O, the direction toward the 2nd end part 9b which is the moving destination of the said coating liquid 33 along the said opening 8a is set to the x-axis. The direction perpendicular to the x-axis from the origin is set to the y-axis (see Figs. 4, 6 and 7).

In addition, the edge part of the width direction of the coating area | region F is the edge part of the width direction of the to-be-coated object 31 in the coating area F. Moreover, as shown to FIG. In addition, the edge part set to origin O is the edge part of the side near the inflow port 10 in the coating area F. As shown in FIG.

In addition, as shown in FIG. 4, FIG. 6, and FIG. 7, the coating liquid 33 which flowed in into the manifold 9 from the inflow port 10 has the plurality in the edge edge 9c arranged in the said width direction. Each virtual path K which flows out from the outflow position of the slot 8 to the slot 8, passes through the slot 8 in a direction parallel to the y-axis, and is discharged from the plurality of ejection positions of the opening 8a (here, K ₀ to K _M , where M is an integer of 1 or more). In the virtual path K _m of the mth (m is an integer of 0 or more) from the origin O, the distance from the origin O to the discharge position is represented by x _m [m], from the inlet 10 to the opening 8a. The total pressure loss of? Is represented by? P _m [Pa], and the distance (slot length) between the outflow position and the ejection position is represented by L _m [m].

At this time, ΔP _m and to the relationship of L _m is represented by a formula (2), (3) and equation (2), (3) while satisfying the respective virtual path K _m each ΔP _m, the virtual path K _m between in and each L _m to the same value each other, calculated from the secondary curve of the following, as a secondary approximate curve of the relationship of x _m in each of L _m and, for each virtual path K calculated plot graph formula (1) Determine.

A, B, C: Coefficient [-]

W: Coating width [m]

Q ₁ : Flow rate of coating liquid flowing into manifold [㎥ / s]

Q ₂ : Flow rate of coating liquid flowing out of manifold other than slot [㎥ / s]

S: flow rate of coating liquid discharged from slot (S = (Q ₁ -Q ₂ ) / W) [m 2 / s]

h: slot height [m]

R: Radius of manifold [m]

n _c: a first viscosity parameters of the coating liquid in the manifold [-]

η _c : second viscosity parameter [-] of the coating liquid in the manifold

n _s : first viscosity parameter [-] of the coating liquid in the slot

η _s : second viscosity parameter [-] of the coating liquid in the slot

The above formulas (1), (2) and (3) will be described below.

The secondary curve represented by the formula (1) draws the shape of the slot side end edge 9c of the manifold 9.

Derivation of such quadratic curves, that is, determination of coefficients A, B, and C will be described later.

Formulas (2) and (3) are formulas calculated based on the following assumptions.

In detail, the coating liquid 33 which flowed into the manifold 9 flows out into the said slot 8 from the several outflow position arrange | positioned at the said width direction in the edge part 9c, and is parallel to a y-axis. It is assumed to follow each virtual path K passing through the slot 8 in the direction and discharged from the plurality of discharge positions of the opening 8a.

Formulas (2) and (3) represent the distance from the origin O to the discharge position in the m-th virtual path K _m from the origin O as x _m [m], and the opening 8a from the inlet 10. The voltage force loss up to) is expressed by ΔP _m [Pa], and when the distance (slot length) between the outflow position and the discharge position is represented by L _m [m], it is a formula showing the relationship between ΔP _m and L _m . In the formulas (2) and (3), the slot height is an interval in a direction perpendicular to the width direction of the opening 8a of the slot 8.

Further, from the origin O (x ₀ [m]), the 0th discharge position is the origin itself, the first discharge position is spaced apart by x ₁ [m], and the second discharge position is spaced apart by x ₂ [m]. ,… , m-th discharge position is spaced apart by x _m [m]. The discharge positions may be spaced apart from each other at equal intervals or may be spaced apart at different intervals. Similarly, each outflow position may also be spaced at equal intervals, or may be spaced at different intervals.

In the present embodiment, for each outlet position and ΔP _m in each virtual path K _m that passes through the supplying position, the equation (2), while satisfying the 3 each ΔP _m is between each virtual path K _m Each L _m is calculated to be the same value as each other.

Moreover, the graph which plotted the relationship between each computed L _m and each x _m corresponding to this is created.

The quadratic approximation curve of the graph thus created is determined as the quadratic curve drawn by the end edge 9c of the manifold 9.

The derivation of the expressions (2) and (3) will be described.

As shown in FIG. 4, when the coating liquid 33 is discharged from the slot 8 of the die 5, it correlates with the discharge position in the width direction of the slot 8 from the common sense of a physical law. Without assuming that the total pressure loss of the coating liquid 33 from the inlet 10 to the opening 8a of the slot 8 is the same between the virtual paths, in any m-th path, (3) holds.

On the basis of the above assumption that the voltage loss is equal regardless of the position of the slot 8 in the width direction, the voltage loss ΔP of the coating liquid 33 introduced from the inlet 10 and discharged from the slot 8 is , And are represented as in the following formulas (4) and (5), and specifically, as shown in the following formula (6). In addition, the pressure loss in the y-axis direction in the manifold 9 is zero. In addition, i is an integer of 1 or more and m or less.

In general, the relationship between the shear rate and the viscosity of the liquid is represented by the following formula (7) using two viscosity parameters.

For the coating liquid 33, the relationship between the shear rate and the viscosity is obtained, and a graph as shown in FIG. 5 is obtained.

Here, if the area of the graph corresponding to the shear rate of the portion passing through the manifold 9 and the area of the graph corresponding to the shear rate of the portion passing through the slot 8 are previously investigated, for example, Two regions are shown in the graph of FIG. 5, respectively. That is, in these two areas, the relationship between the shear rate and the viscosity of the above formula (7) is established.

From this, the relationship between the shear rate and the viscosity when the coating liquid 33 passes through the manifold 9 is represented by the following formula (8). In addition, the relationship between the shear rate and the viscosity when the coating liquid 33 passes through the slot 8 is represented by the following formula (9).

And the assumption that the shape and size of the cross section of the manifold 9 seen from the width direction are the same over the width direction, and the flow velocity of the coating liquid discharged from the opening 8a of the slot 8 are the same over the width direction. (I.e., S ₀ to S _M are the same values), under the assumption, according to equation (6), a known parameter called the viscosity parameter and an unknown slot length (distance between the end edge 9c and the opening 8a). ) using L _m, formulation by the total pressure loss ΔP _m in each virtual path K _m, the equation (2), (3) is obtained.

In the formulas (2) and (3), the pressure loss ΔP _{sm in the} slot 8, the pressure loss ΔP _{cm in the} manifold 9, and the total pressure loss ΔP _m (pressure loss ΔP _{sm in the} slot 8 and The total of the pressure loss ΔP _{cm in} the manifold 9, and in FIG. 4, each of the virtual paths K _m (K ₀ , K ₁ ,) from the 0th to the Mth with respect to P _IN −P _outm = ΔP _m . … K _M ) is shown in FIG. 4. The flow velocity S _m of the coating liquid 33 discharged from the opening 8a is shown like FIG. Slot length is L _m, is represented as shown in FIG.

Then, the total pressure loss ΔP _m is a value equal to each other between the respective virtual path, K _m is a respective slot which the total pressure loss ΔP _m are each the same value between each virtual path K _m in each virtual path K _m in accordance with the assumed The length L _m is calculated. This calculation is performed using the add-in solver of the conventionally well-known table calculation software (for example, "MICROSOFT EXCEL (registered trademark) by Microsoft Corporation). Here, the values that are equal to each other mean values of each other in which an error function indicating the degree (difference) of the value of each other is minimized.

4, 6, and 7 show the shape of the end edge 9c initially set before calculating L _m using the formulas (2) and (3), the width of the workpiece 31. The aspect set to the shape extended linearly in the direction (x-axis direction) is shown. However, the shape of the edge part 9c initially set is not specifically limited, It may be linear or a secondary curve may be sufficient as it.

The quantity of the outflow position and the discharge position (that is, the value of m) through which the virtual path K passes, and the interval Δ _x between the outflow positions and the discharge positions are not particularly limited and can be appropriately set. have.

For example, as the value (quantity of the virtual path) of the quantity m of the said outflow position and the discharge position is large, the coating liquid 33 discharged from the slot 8 over the whole width direction of the to-be-processed object 31 is carried out. While it is possible to make the flow rate more uniform, calculations tend to be complicated.

Therefore, for example, in consideration of this viewpoint, the quantity and interval of the outflow position and the discharge position can be appropriately set.

Moreover, it is preferable that the space | interval of the said outflow position and discharge position is equal intervals.

Each slot length L _m obtained as described above, when the graph of the plot with respect to the distances x _m, for example, be obtained a graph shown in Fig.

If this graph is approximated by a quadratic function, as shown in Fig. 8, a quadratic approximation curve is obtained.

Formula (1) is specifically determined by employ | adopting each coefficient of the obtained 2nd approximation curve to the coefficients A, B, and C in the said Formula (1).

Then, the end edge 9c is formed to follow the determined equation (1). Moreover, the manifold 9 is formed so that the shape and size of the cross section seen from the said width direction may be the same over the width direction in accordance with this edge edge 9c.

In addition, when the coating liquid 33 is a Newtonian fluid, in Formula (1), since A approaches 0, the approximation curve approaches the straight line having the slope. In addition, when the coating liquid 33 is a Newtonian fluid, the viscosity is comparatively low, and the flow volume of the coating liquid 33 discharged from the opening 8a of the slot 8 is comparatively small, A and B are also 0. Since it is close to, the coating liquid 33 is close to a straight line parallel to the x axis.

In addition, as described above, and as apparent from the formulas (2) and (3), since the shape and size of the cross section of the manifold 9 are the same over the width direction (that is, the x-axis direction), The radius R of the cross section of the manifold 9 is also the same over the width direction (that is, the x-axis direction).

As for the radius (radius of a cross section) of such a manifold 9, shape coefficient D is used according to the shape of the cross section of the manifold 9 seen in the moving direction of the coating liquid 33 as shown in FIG. Can be set by the formula of R = D × r. For example, when the shape of the cross section is circular, the radius of the manifold 9 can be used as it is as the radius r of the circle.

On the other hand, when the shape of the cross section is semi-circular or fan-shaped, the radius of the cross section can be set as shown in Fig. 9 by using the shape factor D.

As shown in FIG. 2, the end edge 9d on the side opposite to the slot 8 in the manifold 9 has an end edge such that the interval with the end edge 9c is the same over the width direction. It is formed in the same shape as (9c).

As described above, the coating device 1 according to the present embodiment has the same shape and size of the cross section of the manifold 9 as seen from the width direction over the width direction, and the slot 8 of the manifold 9 is provided. The end edge 9c of the side is formed in the shape which draws the quadratic curve represented by following formula (1), and the relationship of (DELTA ₎ P _m and L _m is shown by following formula (2) and (3), 2 and 3 while satisfying each outflow position and the angle of ejection ΔP at the position _m of each virtual path K calculated for each L _m between _m to the same value to each other, corresponding to each of the calculated L _m, each L _The quadratic approximation curve of the graph plotting the relationship of x _m corresponding to _m , and is configured to determine the quadratic curve.

This configuration will be described. The flow rate of the coating liquid 33 is discharged from the opening (8a) of the manifold 9, the same that homes, each virtual path, the slot (8) in between the K _m is the shape and size of the cross-section across the width direction from the transverse direction Equations (2) and (3) derived based on the assumption that S _m are the same value are used. Then, a known parameter and an unknown distance (slot length) L between the outlet position (end edge 9c on the slot 8 side of the manifold 9) and the discharge position (that is, the opening 8a) L each L _m is calculated ΔP _m, represented by _m to the same value to each other between the respective virtual path K _m. Based on the calculated L _m , a quadratic approximation curve is determined. Then, the end edge 9c on the slot 8 side of the manifold 9 is formed to follow this secondary approximation curve. In accordance with this end edge 9c, the manifold 9 is formed so that the shape and size of the cross section seen from the width direction are the same over the width direction.

By forming the manifold 9 in this way, the flow volume of the coating liquid 33 discharged from the opening 8a of the slot 8 can be made close to the same value over the width direction of the to-be-processed object 31. FIG. have. Thereby, the fluctuation | variation of the thickness of the coating film 35 formed can be suppressed over the width direction.

Moreover, since the said 2nd approximation curve can be determined from a known parameter, it is efficient.

Therefore, the coating film 35 in which the fluctuation | variation of thickness was fully suppressed in the width direction can be formed efficiently.

Next, the manufacturing method of the coating film 35 of this embodiment is demonstrated.

The manufacturing method of the coating film which concerns on this embodiment is the process of forming the coating film 35 by discharging the coating liquid 33 on the to-be-moved coating object 31 using the said coating apparatus 1. It is provided.

According to the said manufacturing method, since the said coating apparatus 1 is used, the coating film 35 in which the fluctuation | variation of thickness was fully suppressed in the width direction can be formed efficiently.

As mentioned above, according to this invention, the coating apparatus and the manufacturing method of a coating film which can form the coating film by which the fluctuation | variation of the thickness fully suppressed in the width direction are provided efficiently are provided.

Although the coating apparatus of this embodiment and the manufacturing method of a coating film are as above-mentioned, this invention is not limited to the said embodiment, It is possible to change a design suitably in the range which this invention intends.

The embodiment shows an embodiment both the coating fluid 33 flows from the inlet 10 is flowing out of the slot (8) (for example, Q ₂ = 0 in FIG. 6). However, in the present invention, for example, as shown in Fig. 10, the manifold 9 allows the coating liquid 33 to flow out of the manifold 9 in addition to the slot 8 ( 12, having a discharge portion 13 which constitutes a path through which the die 5 sends the coating liquid 33 from the discharge port 12 to the outside, and a part of the coating liquid 33 introduced from the inlet 10. May be discharged to the slot 8, and the remaining portion may be discharged from the discharge port 12 through the discharge portion 13.

As shown in FIG. 2, the said embodiment shows the aspect which is located so that the edge part of the coating area F may overlap with the inflow port 10. As shown in FIG. However, in this invention, as shown, for example in FIG. 11 and FIG. 12, the aspect in which the edge part of the coating area F is located inside the inflow port 10 may be employ | adopted. In the aspect shown in FIG. 11, the restriction part 21 which restricts discharge of the coating liquid 33 is arrange | positioned in the width direction both ends of the opening 8a of the slot 8, respectively. The width | variety (coating width W) of the coating area | region F is small by arrange | positioning these control parts 21. FIG.

2, the inlet 10 is formed in the 1st end part 9a of the manifold 9, and the coating liquid 33 which flowed in from the inlet 10 is 1st as shown in FIG. The aspect sent to the 2nd end part 9b from the edge part 9a is shown. However, in the present invention, the position at which the inlet 10 in the manifold 9 is formed may be a position corresponding to the center of the coating region F, for example, as shown in FIGS. 13 to 15. .

In this case, as shown in FIG. 13, FIG. 14, the inflow port 10 is formed in the width direction center part of the to-be-processed object 31 in the manifold 9, and the center of the inflow port is the center of the coating area F. In FIG. The coating liquid 33 introduced from the inlet 10 is directed toward both the first end 9a and the second end 9b (ie, both ends).

At this time, it is assumed that the flow of the coating liquid 33 is linearly symmetrical with an imaginary straight line (not shown) passing through the center of the coating region F and parallel to the y axis. And as shown in FIG. 15, about the coating liquid 33 sent to the 2nd end part 9b downstream from origin O from the origin O as the origin O, each L _m is similarly mentioned above. When it determines, each L _m is similarly determined also about the coating liquid 33 which moves from the origin O toward the other 1st end part 9a. In addition, the center of the coating area F is a position which divides the coating area F in half in the width direction (namely, the moving direction of a coating liquid), and the center of the inflow port 10 makes the inflow port 10 the width direction. It is the position which divides into 1/2.

EXAMPLE

Next, although a test example is given and this invention is demonstrated in more detail, this invention is not limited to these.

Example 1

(Material used)

Coating object: PET (polyethylene terephthalate) film (trade name: diamond, Mitsubishi Chemical Co., Ltd.)

Coating solution: acrylic polymer (trade name: SK Dyne, Soken Chemical Co., Ltd.)

About the coating liquid, the viscosity for each shear rate was measured and graphed according to the following method. From the obtained graph, the 1st and 2nd viscosity parameters of the coating liquid in a manifold, the 1st and 2nd viscosity parameters of the coating liquid in a slot, etc. were measured. The results are shown in Table 1.

(Measuring method of viscosity)

Using a rheometer (form RS1, manufactured by HAAKE) equipped with a jig (a cone plate having a cone diameter of 25 to 50 mm and an angle of cone of 0.5 to 2 °), under a temperature and humidity condition of 23 ° C. and 50% RH, The viscosity of the coating liquid was measured. At this time, each viscosity which changed the shear rate was measured.

The results are shown in FIG. Moreover, the 1st and 2nd viscosity parameters in the manifold and the slot were computed from this result, respectively.

Specifically, in the shear rate-viscosity curve shown in FIG. 16, a range of shear rates corresponding to the flow of the coating liquid in the manifold and the flow of the coating liquid in the slots was determined by preliminary experiments.

By approximating the shear rate-viscosity curve within the range of the determined shear rates to the above formulas (8) and (9), the first and second viscosity parameters n _c , η _c and slots of the coating liquid in the manifold the first and second parameters of the viscosity in the coating liquid _(s n, η _s) was determined, respectively.

(Output of flow rate S)

The flow velocity S was computed by the formula of S = (coating thickness (wet) of the set coating liquid) x (moving speed of a to-be-coated object).

(Determination and Formation of Manifold Shape)

As shown in FIG. 3, the cross section viewed from one side in the width direction is semicircular, and the manifold extends in the width direction as shown in FIG. 4, and has a manifold having a constant shape and size of the cross section over the width direction. Based on the die. In the die, an inlet was formed at the first end of the manifold while no outlet was formed. The shape of the manifold was determined as follows.

Table 1 shows the width of the coating liquid coated on the workpiece, the moving speed of the workpiece (line speed) by the support portion, the flow rate of the coating liquid when flowing into the manifold, the manifold radius, the slot height, and the like. It was set together. Using the formula (2), (3), each virtual slot length to L _m, each total pressure loss ΔP _m, the same value to each other between the respective virtual path K _m of the path K _m passing through each outlet position and a discharge position It was calculated to be. In the calculation, it was used as the value shown in Table 1 as each of 0xFF ΔL _m (L _0).

Then, the relationship between the discharge position on the x-axis and the slot length L _m was plotted and approximated by a quadratic function to obtain a quadratic approximation curve. The results are shown in FIG.

The shape drawn by the obtained 2nd approximation curve was determined as the shape of the slot side edge of a manifold. The manifold was formed such that the shape and size of the cross section of the manifold at the origin O were the same as those throughout the width direction, that is, the shape and size of the cross section of the manifold were constant in the width direction. In this way, a manifold as shown in FIG. 2 was formed.

Coating was performed on the to-be-coated object on the conditions of Table 1 using the die which has the formed manifold. The coated coating solution was dried to form a coating film. The thickness of the obtained coating film was measured using the linear gauge over the width direction. The results are shown in FIG.

As shown in FIG. 18, the coating film in which the fluctuation | variation of the thickness was suppressed over the width direction was obtained.

Comparative Example 1

As shown in FIG. 19, a manifold was produced. Specifically, the slot side end edge of the manifold is straight along the leading edge (the opening of the slot) of the die (ie parallel to the x-axis direction), and the shape and size of the cross section viewed from the width direction, The manifold was produced so that it might become the same over the manifold of Example 1 across the width direction. The slot length L of this manifold was 40 mm, and was the same over the width direction as shown in FIG.

Coating was performed similarly to Example 1 on the conditions of Table 2 using the die which has the produced manifold. The thickness of the obtained coating film was measured over the width direction.

The results are shown in FIG.

As shown in FIG. 21, the thickness of the obtained coating film was fluctuate | varied greatly in the width direction.

Comparative Example 2

In the manifold of the comparative example 1, as shown in FIG. 22, the process was added so that only the slot side end edge might become the same shape (same slot length) as the slot side end edge of Example 1. FIG. In other words, in the manifold of Example 1, the process was added so that the edge of the edge on the opposite side to a slot may become the same shape as the comparative example 1 (refer FIG. 19). The shape of the cross section of this manifold seen from the width direction was semicircular and constant over the width direction. The size of the cross section was larger toward the downstream side in the moving direction of the coating liquid.

Coating was performed similarly to Example 1 using the die which has the produced manifold. The thickness of the obtained coating film was measured over the width direction.

The results are shown in FIG.

As shown in FIG. 23, in the obtained coating film, the fluctuation | variation of the thickness of the width direction was suppressed rather than the comparative example 1, but was larger than Example 1. FIG.

In Comparative Example 2, streaks were generated in the coating film. This reason is that in Comparative Example 2, since the shape of the cross section of the manifold is different in the width direction, the speed change of the coating liquid in the manifold is not uniform in the width direction (not a forging change), and as a result, It is considered that the flow of the coating liquid in the manifold was greatly disturbed.

In contrast, in Example 1, streaks did not occur. The reason for this is that when the shape and size of the cross section of the manifold are the same in the width direction as in Example 1, since the moving speed of the coating liquid in the manifold changes monotonously, the flow of the coating liquid in the manifold is disturbed. I think it was because it was difficult.

1: coating device
5: die
8: slot
8a: opening
9: manifold
9a: first end
9b: second end
9c, 9d: end edge
10: inlet
12 outlet
15: support
17: high fire
31: workpiece
33: Coating solution
35: coating film

Claims (2)

A coating device having a die for coating a coating liquid on a relatively moving workpiece,
The die,
A manifold having an inlet through which the coating liquid flows and sending the coating liquid introduced from the inlet toward the width direction of the workpiece;
Has a slot in communication with the manifold and having an opening at the leading edge of the die,
The shape and size of the cross section of the manifold seen from the width direction are the same over the width direction,
The opening of the slot extends along the width direction,
The end or center of the width direction of the area | region in which the said coating liquid in the said opening is discharged | emitted from the said slot is set as an origin, and the x-axis is set along the opening from the origin in the direction which the coating liquid is sent to, When the y axis is set in the direction perpendicular to the x axis from the origin,
The slot-side end edge of the manifold is formed in a shape drawn by a quadratic curve represented by the following formula (1),
The coating liquid introduced from the inlet into the manifold flows out of the slot side end edge into the slot at a plurality of outflow positions arranged in the width direction and passes through the slot in a direction parallel to the y axis. Is assumed to follow each virtual path discharged from a plurality of discharge positions of the opening,
In the virtual path at the mth (m is an integer of 0 or more) from the origin, the distance from the origin to the discharge position is x _m [m], and the total pressure loss of the coating liquid from the inlet to the opening is ΔP. _m [Pa], when the distance between the outlet position and the discharge position is represented by L _m [m], respectively,
The relationship between the ΔP _m and the L _m is represented by the following formulas (2) and (3),
While satisfying the above formulas (2) and (3), each L _m is calculated such that each ΔP _m in each virtual path is equal to each other between the virtual paths, and each calculated L _m and the corresponding L _m And a quadratic approximation curve of the graph with the relationship of x _m corresponding to.

A, B, C: Coefficient [-]

W: Coating width [m]
Q ₁ : Flow rate of coating liquid flowing into manifold [㎥ / s]
Q ₂ : Flow rate of coating liquid flowing out of manifold other than slot [㎥ / s]
S: flow rate of coating liquid discharged from slot (S = (Q ₁ -Q ₂ ) / W) [m 2 / s]
h: slot height [m]
R: Radius of manifold [m]
n _c : first viscosity parameter [-] of the coating liquid in the manifold
η _c : second viscosity parameter [-] of the coating liquid in the manifold
n _s : first viscosity parameter [-] of the coating liquid in the slot
η _s : second viscosity parameter [-] of the coating liquid in the slot The manufacturing method of a coating film provided with the process of discharging a coating liquid on the to-be-moved object using the coating apparatus of Claim 1, and forming a coating film.

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